Exactly 5 weeks ago, I got a batch of Angraecoid plants from Malala (Madagascar) arranged by a friend who ordered a batch of plants for a number of people (all legal of course, with all the paperwork). I had done this in the past, and often it took a long time for plants to develop new roots and grow on properly. Sometimes 3-4 month and about 1/3 of the plants would not make it. If the plant did not grow on before winter, it would likely not see the next spring.

Just before the plants arrived, I came across an article about Trichoderma which claimed that a) it improved root development, b) it makes plants more resiliant to diseases. I managed to buy a Trichoderma/clay powder to be used for watering and decided to try it.

As usual, the imported plants had hardly any life roots. No roots that were growing.

Steps I normally perform on imported plants

I prepared a sugar or mollassis solution and dipped the green parts of the plants into it

After two days, showered the plants heavily to get all the sugar off (otherwise there will be problems later)

Repot or mount

If the plants are in really bad shape, I spray with AgroBest Envy (an anti transpirant, which can reduces moisture loss in plants). In this case I did.

What I did additionally

I then prepared a Trichoderma solution (using Trichoderma/clay poweder)

I soaked the plants in the solution on March 25th

I watered about every 4-5 days. In effect this meant that the mounted plants got fairly dry: the moss they are in would be bone dry on the surface after 1-2 days (but there would still be some moisture).

Then I forgot about the plants: as expected, they did not produce new growth and there was no visible sign of new root development. I also didn't apply the second dose of Trichoderma 7-10 days later as outlined in the instructions.

Last week, my friend dropped me a line to see how my plants were doing. So I had a closer look: I was amazed to see that half of the plants had developed masses of new roots hidden in the moss. Mainly new roots coming from the base of the plant (see pics, taken after watering such that the roots are more easily visible). In some cases an inch of new roots grew in less than 4 weeks.

The other 50% may have developed roots too, but as they are mounted with spaghnum the root growth is not as visible. I also noticed that all plants are now starting to grow.

Of course this is not scientific, but I am amazed how well and quickly the roots are developing compared to the experience of past years (in particular with plants from Malala). Plants from that source at a minimum took 2-3 months to develop new roots, sometimes new roots would not develop until the next grwoing season or not at all (with the plant dying). Also comparing notes with my friend: her plants have not yet developed new roots.

Note that the roots have a different look to roots on other plants that I have grown on in the past: they have lots of white "hair" on them (in other words the roots are feeder roots).

I gave the plants another soak in Trichoderma solution this morning and I am about to try Trichoderma on the rest of my plants in the greenhouse.

Very interesting. Thanks for posting this information. Iíve heard about beneficial fungi before but Iíve never heard about results first hand. Thereís a commercial grower near me that also uses beneficial bacteria on his seedlings. From what Iíve read, beneficial fungi and bacteria are most effective on seedlings.

Fascinating, Lars, thank you for sharing! I look forward to hearing how the plants do into the future, but such a quick flush of new roots is certainly a great sign. I'll try your method next time I get bareroot plants or deflask seedlings.

Incredible - thanks for sharing. Looking forward to hearing more developments. I refrained from a malala order this year because of such dismal survival...but this gives us some hope! Hope to hear the progress of your plants as it continues, as well as how this works for you in the rest of the greenhouse. Is the source of your trichoderma commercial, or can it not be shared?

Neat to see results on orchids! A colleague at work was using it as one of her study organisms (interactions between plants and beneficial soil dwelling organisms, and how that affects interactions with insects). I would have gotten some Trichoderma inoculum from her, but her contract ended last year.

Where did you buy yours Lars? I'd love to try it too! Apparently seaweed extract works very too at promoting root growth.

you have me in a quandary. I am getting some newly deflasked seedlings from China and have purchased some Physan20 to spray them with. I assume that this product would kill trichoderma ? Now I don't know whether I should just use trichoderma as in one of the links it mentions that trichoderma feeds on other fungus (and I have plenty, it grows on the sphag of my repotted plants, and then disappears) And I am not getting that many to be able to split them and do a 50/50 test.